Quarkonium Resonance Model of the 125 GeV Boson

Abstract

A quarkonium model of the recently discovered X boson at 125 GeV is investigated. Two isosinglet $J^{PC}=0^{-+}$ resonances $\zeta$ and $\zeta'$ mix and their masses are determined by the masses of the bottomonium and toponium eigenstates. This mixing is enhanced by the non-perturbative gluon interaction produced by an axial $U_A(1)$ anomaly. The resonance $\zeta$ is identified with the 125 GeV boson X, while the heavier $\zeta'$ resonance has a mass 230 GeV. We assess the most recent data for the decay mode $X\rightarrow ZZ^*\rightarrow$ 4 leptons with a critical discussion of the determination of the parity of the $X$ boson.